The present invention relates generally to an electrical connector module, and more particularly, to an electrical connector module designed primarily for use in the communications or data transmission industries to provide access to and electrically connect one or more of a plurality of electrical circuits or leads to one or more other such circuits or leads.
In the communications industry, and particularly in the telephone industry, it is often necessary to electrically connect a relatively large number of first circuits or leads with a similar number of second circuits or leads. These are commonly referred to as incoming and/or outgoing leads. As a result of growth, relocation or reassignment, changing of telephone numbers, etc., these electrical connections between the incoming leads and the outgoing leads undergoes change on a regular basis. To facilitate this relatively constant change, the prior art provides circuit access members such as connector panels or terminal blocks. These panels and terminal blocks provide for termination of the incoming and outgoing leads at the rear face of the panel or terminal block. This termination is normally accomplished by conventional techniques such as wire wrap, soldering or the like. The front side of such panel or terminal block provides means for electrically accessing each of the individual incoming or outgoing leads via a connector element. In some cases, this access was provided by a wire wrap pin with the connections between such pins being made via a conventional wire wrap or soldering process. These systems, however, were highly inefficient and time consuming because of the relatively frequent changes in connections required as a result of growth, relocation or reassignment, changes in telephone numbers, etc.
In an effort to overcome the inefficiencies of using a wire wrap process, leads in many of the access members were accessed via a receptacle. A plurality of patch cords of fixed length with patch plugs engageable with the receptacles were then used to access the particular circuits or leads and electrically connect the same with a second circuit or lead. With these patch cords, an incoming lead could be patched or electrically connected to a remotely located outgoing circuit much more efficiently than using a wire wrap or soldering process. In some cases, however, the connectors associated with the circuits desired to be connected were only a few inches apart, while in other cases they were several feet or more apart, thus requiring a substantially longer patch cord. As a result of these differing conditions, a relatively large inventory of different lengths of patch cord had to be kept available in order to accommodate the various distances between the connectors desired to be connected.
Because of these disadvantages, connectors were developed which eliminated the need for patch cords of fixed lengths. These connectors provided means for directly connecting one end of a jumper or connecting wire to a first connector element and means for directly connecting the opposite end of the jumper or connecting wire to a second connector. A tool was also provided for use with these connectors to connect the jumper wire to the connector elements and to sever excess wire after the connection had been made. With these connectors, a single spool of wire could be used to make the various connections desired, thus eliminating the need for maintaining an inventory of patch cords. Two such connectors used for this purpose are identified in U.S. Pat. Nos. 3,518,618 and 4,283,105. Although these connectors were satisfactory in many respects, they inherently embodied several limitations. First, because of their particular configuration and operation, the density of an array of such connectors was limited. Secondly, unlike the connectors utilizing patch plugs and patch cords, the above-described connectors were not insulated. Thus, inadvertent shorting or interference with connected circuits was common as a result of manually brushing across another connector or inadvertently causing a conductive material to come in contact with another connector element. This was and continues to be a particularly serious problem in data transmission circuits where such a short can result in the loss of data. Thirdly, many of the prior art connectors did not provide for the connection of multiple wires to an individual connector without using two patch plugs stacked together. Thus, if it was desired that a particular first lead or circuit be connected to more than one second lead or circuit, a commoning bar or other similar means was necessary. Fourthly, neither of the above connectors provided strain relief means for reducing the possibility of jumper wires being inadvertently pulled from the connectors.
Accordingly, there has been a need in the art for an improved electrical connector module usable in the communications or data transmissions industries which eliminates the disadvantages of having to maintain an inventory of several different lengths of patch cords and which also eliminates the various other limitations of known connectors of the type described above.